Bi-Convex Lens, N-BK7, 50.8 mm Diameter, 500 mm EFL, Uncoated

The KBX178 N-BK7 Bi-Convex Lens is an uncoated, 2 inch (50.8 mm) diameter, N-BK7 bi-convex lens with an effective focal length of 500 mm. It is designed to meet the demanding requirements of laser electro-optic applications. Newport's N-BK7 precision bi-convex lenses are manufactured from fine annealed optical glass and are polished to tight tolerances using master test plates to ensure minimum wavefront distortion.

Specifications

Technical Specs

Lens Shape
Bi-Convex
Diameter
50.8 mm
Lens Material
N-BK7
Antireflection Coating
Uncoated
Surface Quality
40-20 scratch-dig
Surface Accuracy, Irregularity
λ/4
Surface Accuracy, Power
1.5 λ
F/#
9.8
Effective Focal Length (EFL)
500 mm
Back Focal Length (BFL)
498.59 mm
Radius of Curvature (R)
516.098 mm
Edge Thickness (Te)
3.0 mm
Center Thickness (Tc)
4.251 mm

Principal Plane 1 (P1)
1.40 mm
Principal Plane 2 (P2)
-1.40 mm
Design Wavelength
589 nm
Centration
≤3 arc min
Chamfers
0–0.8 mm face width
Chamfers Angle/Tolerance
45° ±15°, typical
Focal Length Tolerance
±1 %
Diameter Tolerance
+0/-0.1 mm
Center Thickness Tolerance
±0.1 mm
Clear Aperture
≥central 90% of diameter
Cleaning
See How to Clean Optics

Lens Shape
Bi-Convex
Diameter
50.8 mm
Lens Material
N-BK7
Antireflection Coating
Uncoated
Surface Quality
40-20 scratch-dig
Surface Accuracy, Irregularity
λ/4
Surface Accuracy, Power
1.5 λ
F/#
9.8
Effective Focal Length (EFL)
500 mm
Back Focal Length (BFL)
498.59 mm
Radius of Curvature (R)
516.098 mm
Edge Thickness (Te)
3.0 mm
Center Thickness (Tc)
4.251 mm

Principal Plane 1 (P1)
1.40 mm
Principal Plane 2 (P2)
-1.40 mm
Design Wavelength
589 nm
Centration
≤3 arc min
Chamfers
0–0.8 mm face width
Chamfers Angle/Tolerance
45° ±15°, typical
Focal Length Tolerance
±1 %
Diameter Tolerance
+0/-0.1 mm
Center Thickness Tolerance
±0.1 mm
Clear Aperture
≥central 90% of diameter
Cleaning
See How to Clean Optics

Resources & Downloads

Related Products

Compatible

Description	Compatibility	Avail.	Price
VLH-3AV-Groove Lens Holder, 0.60 to 3.60 in. Diameter Lenses	UNIVERSAL	In Stock FREE 2-day shipping on thousands of products on Newport.com Learn More	$180
AC-2AVariable Size Lens Mount, 17.8-57.1 mm, Thumbscrew Support Arms	UNIVERSAL	In Stock FREE 2-day shipping on thousands of products on Newport.com Learn More	$78
LCM-2Lens Mount, Self-Centering, 0.125-2.375 in. Diameter Lenses	IMPERIAL	In Stock FREE 2-day shipping on thousands of products on Newport.com Learn More	$305
LP-2APrecision Lens Positioner, 2.0 in., 100 TPI XYθXθY, 80 TPI Z	UNIVERSAL	In Stock FREE 2-day shipping on thousands of products on Newport.com Learn More	$1,110
LH-2AFixed Lens Mount, 2.0 in. (50.8 mm), 8-32 Thread, A-LINE	IMPERIAL	In Stock FREE 2-day shipping on thousands of products on Newport.com Learn More	$37
LT20-30Lens Tube, 2 inch dia. LT Series, 3 inch length	UNIVERSAL	In Stock FREE 2-day shipping on thousands of products on Newport.com Learn More	$48